Refactoring to Typescript...

shared/model.ts

@@ -0,0 +1,62 @@
+//
+// Common
+//
+
+export type CommonProps = 'id' | 'createdAt'
+
+type Opaque<T, K, L extends string = 'opaque'> = T & { _: K; __: L }
+
+type Id<T> = Opaque<string, T, 'id'>
+
+//
+// Users
+//
+
+export type AdministratorRole = 'admin' | 'moderator'
+export type StudentRole = 'student'
+
+export type UserRole = AdministratorRole | StudentRole
+
+export type UserId = Id<User>
+
+export type User = {
+    id: UserId
+    role: UserRole
+}
+
+export function isAdministrator(role: UserRole): role is AdministratorRole {
+    return role !== 'student'
+}
+
+export function isStudent(role: UserRole): role is StudentRole {
+    return role === 'student'
+}
+
+//
+// Problems
+//
+
+export type ProblemId = Id<Problem>
+
+export type Problem = {
+    id: ProblemId
+    content: string
+    createdBy: UserId
+    createdAt: string
+}
+
+//
+// Solutions
+//
+
+export type SolutionStatus = 'pending' | 'rejected' | 'accepted'
+
+export type SolutionId = string
+
+export type Solution = {
+    id: SolutionId
+    sentBy: UserId
+    forProblem: ProblemId
+    content: string
+    status: SolutionStatus
+}